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- Investment cast body with integral saddles for positive mounting
to vertical or horizontal 2" pipe
- Standard flanged instrument x flanged process connections -
optional 1/2" FNPT process connections
- PVC coated directional arrowhead handles with positive stops
and integral PVC skirts which seal against the body to protect
internal parts from contamination
- Multi-purpose 1/4" Bleed Valve allows convenient
depressurization of transmitter or checking for equalizer
leakage while in service
- Drain / Purge connections with 1/4" plugs
- Bonnetless construction with unique tapered plug design
- No metal to metal contact
- Bubble tight seals
- Adjustable packing nut stops interport and stem leakage
- Zeroing function can be adapted to remote actuation
- Integral Steam Heating system optional
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The D/A MM6UC is a universal mounting 3-valve
manifold that performs all the necessary functions of a 3-valve system
by utilizing two 3-way valves working together instead of 3 independent
2-way valves. This sensible concept allows the operator to dial
the desired function rather than manipulating a cluster of independent
valves. The unique design of the UNIMOUNT properly groups and
interlocks the porting to provide automatic fool-proof sequencing,
drastically reducing the costly errors of improper operation
inherent in 3-valve systems.
This same unique manifold excels in the ability to perform as both
a manifold and a sturdy transmitter mount for systems that
require remote mounting to a 2" pipe, direct mounting to the meter run
flanges and direct mounting to an integral orifice block.
The Unimount design allows the completion of all
piping prior to installation of the transmitter. The built in
manifold mounting system permits easy removal of the transmitter
without disturbing the process lines or mounting connections.
The D/A UNIMOUNT - A Truly Universal Instrument Adding an
Extra Dimension of Simplicity, Convenience and Safety to Manifolding
Practices.
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Typical Installations
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Direct Mounting to Meter Run Flanges
- Allows mounting direct to the Meter Run Flanges for a
practical closed coupled system
- Eliminates the need for costly piping and fittings
- Provides an extra stout and compact mounting
system
- Installation is simplified with D/A's unique AAF1
Adjustable Adapter Flanges which allow 1/4 turn adjustments when
screwed into the meter run flanges providing a flush gasketed
surface for mounting the UNIMOUNT. These AAF1 units utilize a simple
side to side sliding adjustment form 1-15/16" to 2-1/4" to
accomodate irregular dimensions between the meter run flanges.
- When required, primary block valves which have 1/2"
FNPT outlets can be installed at the meter run in
front of the UNIMOUNT installation - we simply provide a longer
support bracket.
- The optional 1/2" FNPT rod-out connections with plugs
provide a convenient system to rod-out directly into the meter run
interior.
Direct Mounting to Integral Orifice Block
- Provides a practical and compact mounting and manifolding
system for integral orifice blocks
- Locates the transmitter up and out of the meter run
for ease of servicing
- If desired, the UNIMOUNT can be mounted to a 2" pipe for an
extra sturdy support
- With the rod-out option, the integral orifice block
porting can be conveniently serviced
Remote Mounting to a 2" Pipe
- Allows completion of all piping, construction and
pressure testing without the transmitter
- Provides convenient and easy removal of the transmitter
without disturbing the process lines, connections or
mounting for a safe and sensible installation.
- Eliminates undue strain and fatigue on all
connections and components by locating the transmitter center of
gravity directly above the 2" pipe.
- Flanged process connections provide universal versatility
by:
- Converting directly to 1/2" tube fittings with
D/A's AFT4 Adapter Flanges
- Converting directly to socket weld connections
with D/A's AFSW4 Adapter Flanges
- Converting directly to 1/2" FNPT with D/A's
AFF4 Adapter Flanges or utilizing the transmitter 2-bolt oval
flanges
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Operation
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Normal Mode
Zeroing Mode
Depressurization Mode
Isolation Mode
Equalizer Leakage
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Normal Mode
With both valve handles in the normal position, the MM6UC is in the
normal mode with both process inlets open and the equalizing
port blocked.
Zeroing Mode
By dialing the Zeroing Valve handle to the ZERO position, the MM6UC is
automatically switched to the zeroing mode which completely and
properly prepares the transmitter for zeroing by (1)first blocking one
inlet impulse line and (2) then opening the equalizing port which
bypasses the blocked inlet to equalize the P cell at process
pressure. Because it basically operates like a 3-way valve, this forced
zeroing sequence provides fool-proof operation and safety. After
correcting for zero offset, the transmitter is returned to service by
simply redialing the handle to the NORMAL position which, again,
correctly sequences back to the service mode by closing the equalizer
first and then reopening the blocked inlet.
Depressurization Mode
The first step in depressurizing a transmitter is to equalize the H.P.
and L.P. sides to avoid possible damage to the transmitter. This is
done by dialing the Zeroing Valve to the ZERO position. Next, the
Blocking Valve can be dialed to the DEPRESS position which blocks off
the process pressure allowing both cavities of the transmitter to be
simultaneously depressurized thru the common vent valve.
Isolation Mode
By dialing the Zeroing Valve and Blocking Valve handles to the ZERO and
BLOCKED positions respectively, the MM6UC is automatically switched to
the islolation mode where both inlets are blocked and the
equalizing port is closed. The transmitter is now safely isolated and
prepared for field servicing, recalibration or removal. The transmitter
is returned to service by simply redialing the handles to their NORMAL
positions which, again, correctly sequences back to the service mode by
leaving the equalizer blocked and reopening both inlets.
Testing for Equalizer Leakage
Equalizer leakage can be checked by leaving the Zeroing Valve in the
NORMAL position and dialing the Blocking Valve to the BLOCKED position.
In this mode, the equalizers on the 3-way Zeroing Valve and 3-way
Blocking Valve are both closed. The cavity between these blocked
equalizers can now be vented to check for leakage. If leakage is
detected, slightly tighten the Zeroing Valve packing nut.
Note: Because of the unique fool-proof design,
the Zeroing Valve and Blocking Valve handles can be dialed to their
respective positions in any order without causing improper operation.
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Specifications
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Max Ratings:
Teflon:
6000psi @ -150ºF to 150ºF
2500psi @ 220ºF
Connections:
Flanged instrument x Flanged process
Design Codes:
ANSI B31.1, B16.5, NACE MR-01-75(special
order)
Material Codes:
Barstock, A479 - 316, A276-316;
Cast, ASTM-A743 CF3M, ASTM-A-351 CF3M, A 276-316.
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Materials of Construction:
Body: Investment cast 316SS or low grade (non-certified) SS
Wetted Plug: 316SS
Plug Liner: Teflon or Glass Filled Teflon
Face Seals: Ryton reinforced Teflon
Non-Wetted Trim: 303SS
Handle: Cast aluminum arrowhead - PVC coated
Plugs / Bleed Valve:303SS
Exotic materials: Hastelloy C, Monel, Alloy 20,
etc. consult factory.
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